Cannot read properties of undefined (reading 'startsWith')

This error message is usually caused when you try to access a property or method of an undefined value. In this specific case, you are trying to call the `startsWith` method on an undefined value.

Here's an example of how this error can occur:

let str;
if (str.startsWith('Hello')) {
  console.log('Greeting found!');
}

In this example, `str` is undefined, so when we try to call the `startsWith` method on it, we get the error message "Cannot read properties of undefined (reading 'startsWith')".

To fix this error, you need to make sure that the value you are trying to access the property or method on is not undefined. You can do this by checking if the value exists before trying to use it, like this:

let str;
if (str && str.startsWith('Hello')) {
  console.log('Greeting found!');
}

In this updated example, we first check if `str` exists before trying to call the `startsWith` method on it. If `str` is undefined, the `if` statement will return false and the error will be avoided.